The present invention relates to a method and apparatus for feeding solid particulate material into a plenum chamber. More particularly the invention relates to improvements in methods and apparatus which can be utilized with advantage to feed charges of finely comminuted solid fuel particles (e.g., coal) to a gasification chamber which contains oxygen and wherein the particles are oxidized, either entirely or in part. Such methods and apparatus can be resorted to in the production of gaseous fuels which are used in households and/or for other purposes.
It is known to feed solid fuel particles into a highly pressurized gasification chamber by resorting to a system of locks wherein a receptacle or bunker must be filled with compressed inert gas prior to transfer of a charge of fuel particles into the chamber, and decompressed prior to admission of a fresh charge by gravity flow. The pressure of the gas (e.g., nitrogen) which is evacuated from the receptacles of such conventional systems is reduced to atmospheric prior to renewed compression for readmission into the receptacle. This contributes to extremely high energy requirements of the system. Moreover, the gas which is being permitted to expand during and subsequent to evacuation from the receptacle performs no useful work.